How to use the calculator
To use the Odds Converter Calculator, simply enter your odds in any of the supported formats—Decimal, American, Fractional, Hong Kong, or Implied Probability—and the tool will instantly convert them into all other formats in real time. The pop-out option lets you keep the calculator open in a separate window while browsing or placing bets, making it easy to compare and convert odds on the fly.
Understanding the different odds formats
When betting online, odds can appear in a variety of formats depending on the region or bookmaker. Each represents the same thing — the likelihood of an outcome and how much you stand to win — but they’re expressed differently. Our Odds Converter Calculator helps you instantly switch between them. Here’s a quick breakdown of each format included in the converter.
1. Decimal odds
Used in: Europe, Canada, Australia
Example: 2.50
Decimal odds show the total return per unit staked, including your original bet.
- A €10 bet at 2.50 returns €25 (€15 profit + €10 stake).
- The formula:
Return = Stake × Decimal Odds - To find the implied probability:
Probability (%) = 100 ÷ Decimal Odds
Decimal odds are the simplest and most common format for online betting platforms.
2. American odds (Moneyline)
Used in: United States
Example: +150 or -200
American odds are based around winning or risking 100 units.
- Positive odds (+) show how much profit you’d make on a $100 bet.
- Example: +150 means a $100 bet returns $250 total ($150 profit + $100 stake).
- Negative odds (-) show how much you need to bet to win $100 profit.
- Example: -200 means you must bet $200 to win $100 profit.
To convert to decimal:
- For positive odds: (Odds ÷ 100) + 1
- For negative odds: (100 ÷ |Odds|) + 1
3. Fractional odds
Used in: United Kingdom, Ireland
Example: 5/2
Fractional odds express the profit relative to the stake.
- 5/2 means for every 2 units wagered, you profit 5 units.
- A £10 bet at 5/2 returns £35 (£25 profit + £10 stake).
- The formula for implied probability:
Probability (%) = Denominator ÷ (Numerator + Denominator) × 100
Fractional odds are traditional in horse racing and older UK bookmakers but are less common online today.
4. Hong Kong odds
Used in: Hong Kong, parts of Asia
Example: 1.50
Hong Kong odds show profit per unit staked, similar to fractional odds but in decimal form.
- A stake of 1 unit at 1.50 returns 2.50 total (1.50 profit + 1 stake).
- The formula to convert to decimal is simple:
Decimal Odds = Hong Kong Odds + 1
5. Implied probability (%)
Used universally
Example: 40%
Implied probability represents the likelihood of an event occurring based on the odds.
It’s a key metric for identifying value bets and comparing across markets.
- Formula (from decimal odds):
Probability (%) = 100 ÷ Decimal Odds - Formula (to decimal odds):
Decimal Odds = 100 ÷ Probability (%)
Understanding this value helps bettors see through different odds formats and focus on the true risk versus reward.
Summary
Format | Region | Example | Expresses | Conversion to Decimal |
|---|---|---|---|---|
Decimal | Europe / Global | 2.50 | Total return | — |
American | USA | +150 / -200 | Profit on $100 or stake to win $100 | +odds: (odds/100)+1-odds: (100/ |
Fractional | UK / Ireland | 5/2 | Profit : Stake | (num/den)+1 |
Hong Kong | Asia | 1.50 | Profit per unit | +1 |
Probability | Global | 40% | Likelihood of outcome | 100 ÷ decimal |
Each of these formats reflects the same underlying probability — just in different expressions. Our Odds Converter Calculator makes it effortless to switch between them in real time, whether you’re analyzing markets, tracking line movement, or comparing value across bookmakers.